(There is a battle, or battles, against Israel, involving someone called, “Gog”   -   First, said to Ezekiel:)

 

Ezekiel 38:1 And the word of the LORD came unto me, saying,

  2 Son of man, set thy face against Gog, the land of Magog, the chief prince of Meshech and Tubal, and prophesy against him,

  3 And say, Thus saith the Lord GOD; Behold, I am against thee, O Gog,s the chief prince of Meshech and Tubal:

  4 And I will turn thee back, and put hooks into thy jaws, and I will bring thee forth, and all thine army, horses and horsemen, all of them clothed with all sorts of armour, even a great company with bucklers and shields, all of them handling swords:

  5 Persia, Ethiopia, and Libya with them; all of them with shield and helmet:

  6 Gomer, and all his bands; the house of Togarmah of the north quarters, and all his bands: and many people with thee.

  7 Be thou prepared, and prepare for thyself, thou, and all thy company that are assembled unto thee, and be thou a guard unto them.

  8 After many days thou shalt be visited: in the latter years thou shalt come into the land that is brought back from the sword, and is gathered out of many people, against the mountains of Israel, which have been always waste: but it is brought forth out of the nations, and they shall dwell safely all of them.

  9 Thou shalt ascend and come like a storm, thou shalt be like a cloud to cover the land, thou, and all thy bands, and many people with thee.

  10 Thus saith the Lord GOD; It shall also come to pass, that at the same time shall things come into thy mind, and thou shalt think an evil thought:

  11 And thou shalt say, I will go up to the land of unwalled villages; I will go to them that are at rest, that dwell safely, all of them dwelling without walls, and having neither bars nor gates,

  12 To take a spoil, and to take a prey; to turn thine hand upon the desolate places that are now inhabited, and upon the people that are gathered out of the nations, which have gotten cattle and goods, that dwell in the midst of the land.

  14 Therefore, son of man, prophesy and say unto Gog, Thus saith the Lord GOD; In that day when my people of Israel dwelleth safely, shalt thou not know it?

  15 And thou shalt come from thy place out of the north parts, thou, and many people with thee, all of them riding upon horses, a great company, and a mighty army:

  16 And thou shalt come up against my people of Israel, as a cloud to cover the land; it shall be in the latter days, and I will bring thee against my land, that the heathen may know me, when I shall be sanctified in thee, O Gog, before their eyes.

 

(Then, seen by John:)

 

Revelation 20:7 And when the thousand years are expired, Satan shall be loosed out of his prison,

  8 And shall go out to deceive the nations which are in the four quarters of the earth, Gog and Magog, to gather them together to battle: the number of whom is as the sand of the sea.

  9 And they went up on the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down from God out of heaven, and devoured them.

 

(There are different teachings on the timing of this:

1.      at the beginning of, or just before, the tribulation

2.      at the very end of the tribulation

3.      after the thousand year kingdom

4.      dual fulfilment: at the very end of the tribulation and also after the thousand year kingdom

5.      generic allegories describing the enemies of Israel

There are also different teachings on the identity of Gog:

1.      the leader of Russia

2.      the fallen celestial prince over Asia Minor, i.e. Turkey

3.      the antichrist

4.      the devil

5.      a combination of some of the above